Interpretation of normal-deformed bands in Lu167

Abstract

With the aim to get a general understanding of rotational bands in the deformed rare-earth region or in deformed nuclei in general, the observed normal-deformed rotational structures in $^{167}$Lu are interpreted within the unpaired and paired cranked Nilsson-Strutinsky formalisms, CNS and CNSB. Particular attention is devoted to the band crossings. For this nucleus with the Fermi surface high up in the $h_{11/2}$ shell, we conclude that except for the paired AB and BC crossings in configurations with an even and odd number of $i_{13/2}$ neutrons, respectively, the observed band crossings can be understood within the unpaired formalism. Especially, it means that above the AB and BC crossings, the evolution with spin is described as a gradual alignment of the spin vectors of the particles outside closed shells. Consequently, the configurations can be characterized by the number of particles occupying open $j$-shells or groups of $j$-shells. In the present study, we revise the interpretation of some experimental bands and also the nature of the crossings while some previous configuration assignments are confirmed.